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We show that computer-generated diffractive optical elements can be used to synthesize the infrared spectra of important compounds, and we describe a modified phase-retrieval algorithm useful for the design of elements of this type. In particular, we present the results of calculations of diffractive elements that are capable of synthesizing portions of the infrared spectra of gaseous hydrogen fluoride (HF) and trichloroethylene (TCE). Further, we propose a new type of correlation spectrometer that uses these diffractive elements rather than reference cells for the production of reference spectra. Storage of a large number of diffractive elements, each producing a synthetic spectrum corresponding to a different target compound, in compact-disk-like format will allow a spectrometer of this type to rapidly determine the composition of unknown samples. Other advantages of the proposed correlation spectrometer are also discussed. Key words: Synthetic spectra, correlation spectroscopy, diffractive optics, infrared spectroscopy.

Aim: To analyze malpractice trials in radiation oncology and assess how ASTRO APEx® and RO-ILS™ apply to such cases.Methods: The Westlaw database was reviewed using PICOS/PRISMA methods. Fisher's exact and Mann-Whitney U tests were used to find factors associated with outcomes.Results: Of 34 cases identified, external beam was used in 26 (77%). The most common factors behind malpractice were excessive toxicity (80%) and lack of informed consent (66%). ASTRO APEx pillars and ROI-LS had applicability to all but one case. Factors favoring the defendant included statute of limitations (odds ratio: 8.1; 95% CI: 1.3-50); those favoring the plaintiff included patient death (odds ratio: 0.7; 95% CI: 0.54-0.94).Conclusion: APEx and RO-ILS are applicable to malpractice trials in radiation oncology. [ABSTRACT FROM AUTHOR]

PURPOSE: To document survival for patients treated with stereotactic radiosurgery (SRS) for brain metastases either at initial presentation or for salvage in conjunction with other known prognostic factors. METHODS: All patients treated for brain metastasis with SRS (January 2006–October 2013) were reviewed. We identified 150 patients treated for either first brain metastatic event (FBME) or second brain metastatic event (SBME), excluding 14 patients who received SRS for both. Age, gender, primary cancer type, presence of extracranial metastases, number of brain metastases, initial site of metastases, recursive partitioning analysis (RPA), and Karnofsky performance status (KPS) were documented. RESULTS: Primary cancers included lung (n = 83), breast (n = 20), melanoma (n = 13), and other (n = 34). Patients treated with SRS for FBME were significantly older (63.59 yr vs 58.78 yr; P = .03) with a higher RPA index (38.3% vs 19.5% RPA 3; P = .0002), greater female predominance (61% vs 37%; P = .0035), and more primary melanoma (15.6% vs 1.4%; P = .014) compared with those treated for SBME. There was no significant difference in 1-year (29%) and 2-year (12%–13%) actuarial or median survival (5.95 mo and 6.77 mo, respectively) for patients treated with SRS for FBME vs SBME. A Cox regression model revealed KPS and RPA to be significant at the P < .05 level for survival. Multivariable analysis utilizing manual backward selection considering all factors revealed RPA (P = .007) and KPS (P ≤ .001) to be the only independent prognostic factors for survival. Patients with RPA 1 had a 62% decreased hazard of death vs those with RPA 3, with 1-year survival rates for RPA 1, RPA 2, and RPA 3 patients of 36.5%, 33.3%, and 17.1%, respectively. CONCLUSIONS: Despite better performance status noted for patients treated with SRS for FBME compared with SBME, no difference in survival was noted. Aggressive treatment should be considered for patients with high performance status, regardless of whether they present with FBME or SBME. [ABSTRACT FROM AUTHOR]

INTRODUCTION: The use of stereotactic body radiation therapy (SBRT) for treatment of breast cancer oligometastases is being studied by the NRG Oncology Group for toxicity (trial BR001) and survival (trial BR002). Outcome data and prognostic factors for breast cancer oligometastases treated with SBRT, however, are lacking in the literature. METHODS: Between November 2007 and December 2014, a total of 39 women were treated with SBRT/stereotactic radiosurgery (SRS) for oligometastases, defined as < 4 sites of disease. Ninety-seven percent of patients were previously treated with systemic therapy. Median time to SBRT from presentation of metastatic disease was 14.3 months (range: 0–103 mo). SBRT was delivered utilizing the CyberKnife system, with a median dose of 20 Gy (range: 15–60 Gy), a median of 3 fractions (range: 1–5) and 136 beams (range: 68–227), and a median clinical target volume (CTV) of 7.7 cm3 (range: 0.2–135 cm3). Sites of SBRT/SRS (n = 50) included lung (n = 5), bone (n = 14), liver (n = 3), lymph node (n = 6), brain (n = 20), adrenals (n = 1), and chest wall (n = 1). Receptor status included triple-negative (n = 11), human epidermal growth factor receptor 2 (HER2)-positive (n = 11), and estrogen receptor (ER)- or progesterone receptor (PR)-positive + HER2-negative (n = 17). Actuarial/median survival statistics and log-rank P values were calculated. RESULTS: Median survival following SBRT for the entire group was 14.56 months, with 1-year and 2-year actuarial survival rates of 53.8% and 38.5% respectively. Prognostic factors evaluated for survival included brain vs other sites, Eastern Cooperative Oncology Group performance status 0 vs 1–3, number of metastases 1–2 vs > 2, age ≤ 50 years vs > 50 years, and receptor status triple-negative vs HER2+ vs ER+ or PR+/HER2−. Only brain metastases (P = .18) and HER2+ receptor status (P = .04) reduced median survival from 23.2 months and 20.7 months, respectively, to 10.5 months for both groups. CONCLUSIONS: We document survival and prognostic factors of SBRT for breast cancer oligometastases in a single institution. Information about the survival benefit of SBRT following chemotherapy awaits the results of the phase II/III NRG BR002 trial. [ABSTRACT FROM AUTHOR]

INTRODUCTION: Radiation therapy (RT) of orbital tumors is challenging due to surrounding radiosensitive structures. We review our experience with stereotactic body RT (SBRT) for orbital tumors, to describe doses to organs at risk (OARs) and acute toxicity. METHODS: Between August 2006 and August 2014, a total of 41 patients (43 orbits) treated with SBRT for orbital tumors were reviewed. Primary tumor included lymphoma/leukemia (n = 15), recurrent nonmelanoma skin cancer with orbital invasion (n = 9), recurrent melanoma (n = 10), breast metastases (n = 5), and primary lacrimal gland cancer (n = 2). SBRT was delivered utilizing the CyberKnife system with a median dose of 20 Gy (range: 13.5–35 Gy), 5 fractions (range: 3–5), 146 beams (range: 40–227), and clinical target volume (CTV) of 14.8 cm3 (range: 2.3–104.8 cm3). Acute toxicity type and grade within 3 months of SBRT as per the Radiation Therapy Oncology Group (RTOG) guidelines were recorded. RESULTS: The median CTV maximum dose was 27.6 Gy (range: 19.2–48.6). The median optic nerve maximum dose was 14.4 Gy (range: 2.2–36.5 Gy), optic chiasm maximum dose was 5.3 Gy (range: 0.92–28.8 Gy), brain/brainstem maximum dose was 12.5 Gy (range: 1.3–25.5 Gy), lens maximum dose was 16.5 Gy (range: 1.75–28.4 Gy), and globe maximum dose was 20.4 Gy (range: 0.3–44.6 Gy). Thirty-four patients were evaluable for acute toxicity within 3 months of SBRT. Eleven patients noted no acute toxicity (32.4%). Eleven patients experienced conjunctivitis (32.4%); six patients noted foreign body sensation/irritation of eye (17.6%); five patients had acute periorbital edema (14.7%); four had increased tearing (11.8%); two experienced hair loss (5.9%); two developed dry eye (5.9%), with one requiring eye drops; and one experienced pain (2.9%). Only three patients required oral steroids for treatment of acute toxicity. The rate of RTOG grades 1 and 2 acute toxicity was 67.6%. No patients had RTOG acute grade ≥ 3 toxicity. All acute toxicities recorded resolved by 3 months of follow-up. There was no correlation between acute toxicity and CTV maximum dose or CTV. CONCLUSIONS: Acute toxicity is common after SBRT for orbital tumors but is short-lived and mild. Chronic toxicity will be reported with further follow-up. [ABSTRACT FROM AUTHOR]

OBJECTIVES: The primary goal of this study is to determine prognostic factors associated with freedom from biochemical failure (FFBF) and survival for men with localized prostate cancer treated with intensity-modulated radiation therapy (IMRT) in a community hospital setting according to the new National Comprehensive Cancer Network (NCCN) 2015 risk stratification guidelines. METHODS: A total of 228 consecutive men treated with IMRT for organ-confined prostate cancer at Delaware County Memorial Hospital from 2003—when the IMRT program began—to 2012 were reviewed in this institutional review board–approved retrospective study. Biochemical failure was assessed using the Phoenix Nadir +2 definition (a rise by ≥ 2 ng/mL above the nadir prostate-specific antigen level). Toxicity was assessed using the Radiation Therapy Oncology Group group criteria with modification. RESULTS: Ten-year actuarial FFBF for the entire group was 83.18%. Ten-year actuarial FFBF, stratified by 2015 NCCN risk stratification, was 95.2% for very-low-risk, 96.3% for low-risk, 81.5% for intermediate-risk, and 75.4% for high-risk patients. Eight-year actuarial FFBF was 38.7% for the very-high-risk group. Multivariable analysis revealed that only the five NCCN risk groups were independent predictors of FFBF. Ten-year actuarial survival for the entire group was 61.14%. Ten-year actuarial overall survival (OS), stratified by 2015 NCCN risk stratification, was 68.80% for very-low-risk, 81.47% for low-risk, 67.24% for intermediate-risk, 46.30% for high-risk, and 54.93% for very-high-risk men. Ten-year OS rates, stratified by age, were 75.92% for age ≤ 71.5 years and 55.19% for age > 71.5 years. Multivariable analysis revealed that only age was an independent significant factor for survival, with P = .0008. CONCLUSIONS: IMRT use in a community hospital is equally as efficacious and minimally toxic as it is in leading academic institutions. Age at diagnosis was the only significant predictor of survival, suggesting that cancer-specific mortality is minimal after IMRT in localized prostate cancer. [ABSTRACT FROM AUTHOR]

PURPOSE: To comprehensively analyze federal and state court records of malpractice trials related to radiation oncologists and characterize factors important in determining outcomes. METHODS: We systematically reviewed the Westlaw database using the advanced search function, from 1985 to 2015. The outcome measures were (1) dismissal of a case (ie, no trial initiated) and (2) patient receiving indemnity payment, either by jury or settlement. Covariates included treatment modality, alleged malpractice claim, rationale of defendants, characteristics of plaintiffs and defendants, and county-level data from the Area Health Resource Files. Fisher’s exact and Mann-Whitney U tests were used; odds ratios (ORs) with 95% confidence intervals (CIs) were calculated. RESULTS: There were 34 cases identified. Litigation cases at highest risk of nondismissal involved male patients (OR, 0.17 [95% CI, 0.03–0.72]; P = .03) with prostate or head and neck cancers (OR, 0.15 [95% CI, 0.04–0.81]; P = .03) where there is failure to recognize the claim (OR, 0.22 [95% CI, 0.05–0.98]; P = .046) or patient death (OR, 0.70 [95% CI, 0.54–0.94]; P = .04). Statute of limitations (OR, 8.1 [95% CI, 1.3–50]; P = .02) and insufficient evidence (P = .04) defenses were predictive of case dismissal and jury ruling in favor of the radiation oncologist, respectively. Type of radiation therapy (RT) used, specialists involved, academic vs private practice setting of the defendants, resident involvement, and county-level data were not predictive of case dismissal, award, or settlement. CONCLUSIONS: To promote legal decisions in favor of the radiation oncologist, we recommend: accreditation by the American Society for Radiation Oncology (ASTRO) Accreditation Program for Excellence (APEx); use of the ASTRO Radiation Oncology Incident Learning System (RO-ILS); and physician-patient discussion about treatment toxicity (eg, timing, etiologies, and risk of morbidity and mortality), with diligent documentation. [ABSTRACT FROM AUTHOR]

Aim: To analyze malpractice trials in radiation oncology and assess how ASTRO APEx ® and RO-ILS™ apply to such cases., Methods: The Westlaw database was reviewed using PICOS/PRISMA methods. Fisher's exact and Mann-Whitney U tests were used to find factors associated with outcomes., Results: Of 34 cases identified, external beam was used in 26 (77%). The most common factors behind malpractice were excessive toxicity (80%) and lack of informed consent (66%). ASTRO APEx pillars and ROI-LS had applicability to all but one case. Factors favoring the defendant included statute of limitations (odds ratio: 8.1; 95% CI: 1.3-50); those favoring the plaintiff included patient death (odds ratio: 0.7; 95% CI: 0.54-0.94)., Conclusion: APEx and RO-ILS are applicable to malpractice trials in radiation oncology.